Cuckoos in Sri Lanka

by K.G.H. Munidasa

Eleven forms of Parasitic Cuckoos are known to occur in Sri Lanka and out of these only five have been admitted into the checklist as breeding residents. A sixth, the Indian Cuckoo Cuculus micropterus has been labelled ornithologists as a bird with an uncertain status, although there is evidence that occasionally, at least, it breeds in the island, and its young have been found in the nest of the Ceylon black-headed Oriole. For instance, on April 5, 1980 a gem-prospector observed a young bird being fed by a pair of black-headed Orioles at a place called Weli-Ara in Elahera. On impulse, he captured the young and placed it in an improvised cage, under the impression that it was a young hawk of sort.

Subsequently, the man carried the young bird in a cardboard box to Avissawella, his hometown and raised it as a pet weaned on dry fish and prawns, soaked in water.On April 11, I got an opportunity to examine the young bird. It was full fledged and able to fly for short distances. It measured 7.5 inches in length with wings 5 ins. (angle to tip) and possessed zygodactyle feet (two toes pointing forward and two backwards), a differentiating feature in all true cuckoos.

G.M. Henry 's Guide to the Birds of Ceylon, first Edition, 1955 states that the status of this cuckoo is somewhat doubtful, though there is evidence that occasionally, at least, it breeds in the island, the young having been found in the nest of the Ceylon Black-headed Oriole, while W.W.A. Phillips in 1955 revised checklist adds, “The Indian Cuckoo is known to victimise the black-headed Oriole Oriolus xanthornus ceylonensis.”

Local crows

The best known of all resident cuckoos is the Indian Koel or Avurudu-Koha which is parasitic on the two local crows i.e. House Crow and Black Crow. The Koel's egg is described as being greyish-green in ground colour and speckled with reddish-brown. It measures 30.6x22.9 mm against 36x27 mm. In House Crow and 42x29 mm. In Black Crow. The crows eggs however, are said to be brighter in ground colour.

The Ceylon Hawk-Cuckoo and the Pied Crested Cuckoo are both parasitic species which, as far as the records show, victimise the common Ceylon Babbler or the “Seven Sisters”, as popularly known. Both these cuckoos lay turquoise-blue eggs which tally closely with those of the host species. The Indian mainland race of the former is also said to cuckold small birds like Pipits and Chats, while the latter Bulbuls, Laughing Thrushes or various members of the Babbler family.

The Pied Crested Cuckoo has no well defined breeding season, but this generally coincides with the breeding period of the host species Babblers. At such times two or even three cuckoo eggs may be taken from a single babbler's nest. The cuckoo eggs take a slightly different shade and measures 24x19 mm. Against 23.8x18 mm. in the common Babbler.

Babbler

In 1968 in the Ampara District I came across a baby Pied Crested Cuckoo being brought up by the common Babbler. There were between five to six babblers in the group and while two of them attended to the foster child, the rest foraged in the undergrowth. The baby cuckoo was unlike any young babbler that even a inexperienced bird student would have at once noticed the difference. It was grey and buff-white with dirty white wing patches (white in the adult cuckoo) clearly visible on the side of the wings.

Since the adult Ceylon Drongo-Cuckoo closely resembles the Ceylon Common Drongo it was formerly believed that it deposited its eggs in the nest of that Drongo. However, W.E. Wait later obtained authentic evidence that went to prove that in its breeding habits the Ceylon Drongo Cuckoo victimised the black-fronted Babbler Alcippe atriceps siccatus. In 1917 he recovered a nest of the babbler in the Puttalam District, which was tenanted by a nestling of the Drongo Cuckoo. On a previous occasion he had taken a strange egg from a nest of the same species of babbler, which he tentatively assigned to the Drongo Cuckoo.In June 1970 at Muwangala in the Gal Oya Valley, I examined a nest of the White-Throated Babbler in a patch of shrub. It contained a clutch of three speckled eggs of which two were identical in all respect but the other was seemingly different in shape, being very elliptical. Back home I examined the two egg specimens under a bright light.

Though the ground colour of both the eggs was white, in hand the “strange egg” gave out a pink glow, the other being chalky-white. The first egg measured 16x13 mm. Against 18x13 mm. of the second. Henry gives the measurements for the white-throated Babbler egg as 18x13.7 mm. and glossy white in ground colour, with speckles of brownish-red.

In May ‘1975 Shirley Perera of the Department of Wildlife Conservation watched a juvenile of the Drongo Cuckoo being fed by the white-throated Babblers in a jungle area near Mullegama off Inginiyagala. It is on record that about 25 years ago a nestling of this cuckoo was found in a nest of the White-browed Prinia, a bird of the Warbler family, not larger than the Ceylon Tailor-Bird. The white-browed Prinia lays turquoise-blue eggs marked with spots and blotches of chocolate-brown. G.M. Henry suggests that the Drongo Cuckoo may also possibly lay in the nest of the Ceylon Common Iora which builds a cup-like nest usually in an open dead branch.